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1.
J Hazard Mater ; 479: 135727, 2024 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-39244980

RESUMO

The widespread prevalence of microplastics (MPs) in the environment poses concerns as they are vectors of antibiotic resistance genes (ARGs). The relationships between antibiotic resistomes and MPs remain unexplored in soil which was considered as the reservoirs of MPs and ARGs. This study investigated the effects of polyvinyl chloride (PVC) MPs on soil bacterial communities and ARG abundance which soil samples sourced from 20 provinces across China. We found that PVC significantly influences soil bacterial community structure and ARG abundance. Structural equation modeling revealed that PVC alters soil characteristics, ultimately affecting soil bacterial communities, including ARG-containing bacterial hosts, and the relative abundance of ARGs. This study enhances our understanding of how MPs influence the proliferation and hosts of ARGs within diverse soil environments, offering crucial insights for future strategies in plastic management and disposal.


Assuntos
Bactérias , Resistência Microbiana a Medicamentos , Genes Bacterianos , Microplásticos , Cloreto de Polivinila , Microbiologia do Solo , Poluentes do Solo , Microplásticos/toxicidade , China , Poluentes do Solo/toxicidade , Resistência Microbiana a Medicamentos/genética , Bactérias/genética , Bactérias/efeitos dos fármacos , Metagenômica , Farmacorresistência Bacteriana/genética
2.
Mar Environ Res ; 202: 106744, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39288544

RESUMO

Marine pollutants, especially potentially toxic elements (PTEs), increasingly threaten the ecological environment and fishery resources of the Beibu Gulf due to their bioaccumulative nature, toxicity, and persistence. However, the occurrences of multiple PTEs in marine invertebrates within this region remains unclear. Hence, a total of 18 species of commercially harvested invertebrates (shrimp, crab, cephalopod, shellfish, and sea cucumber) were collected from the Beibu Gulf, and the concentrations of nine important PTEs (As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, and Zn) were examined. Subsequent stable isotope analysis for δ13C and δ15N facilitated investigations into biomagnification and human health risk assessment. The results showed that, except for As, the concentrations of the PTEs in the invertebrates were below the national safety limits. Furthermore, significant positive correlations were found between trophic levels (TLs) and log-transformed concentrations of As (P < 0.001, R2 = 0.20) and Cr (P < 0.001, R2 = 0.13), indicating biomagnification of these two metals across trophic positions among species. Finally, the human health risk assessment revealed that the consumption of cephalopod, shellfish, and sea cucumber poses a higher risk of adverse effects compared to shrimp and crab.

3.
Nat Commun ; 15(1): 7179, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39169004

RESUMO

The insufficient availability and activity of interfacial water remain a major challenge for alkaline hydrogen evolution reaction (HER). Here, we propose an "on-site disruption and near-site compensation" strategy to reform the interfacial water hydrogen bonding network via deliberate cation penetration and catalyst support engineering. This concept is validated using tip-like bimetallic RuNi nanoalloys planted on super-hydrophilic and high-curvature carbon nanocages (RuNi/NC). Theoretical simulations suggest that tip-induced localized concentration of hydrated K+ facilitates optimization of interfacial water dynamics and intermediate adsorption. In situ synchrotron X-ray spectroscopy endorses an H* spillover-bridged Volmer‒Tafel mechanism synergistically relayed between Ru and Ni. Consequently, RuNi/NC exhibits low overpotential of 12 mV and high durability of 1600 h at 10 mA cm‒2 for alkaline HER, and demonstrates high performance in both water electrolysis and chlor-alkali electrolysis. This strategy offers a microscopic perspective on catalyst design for manipulation of the local interfacial water structure toward enhanced HER kinetics.

4.
ACS Appl Mater Interfaces ; 16(34): 45197-45206, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39150429

RESUMO

There is an urgent need for faster, brighter, and more controllable scintillation materials in advanced nuclear medicine, high-energy physical experiments, and dark matter particle detection. Nevertheless, the trade-off between high emission efficiency and fast timing characteristics remains a common challenge in the entire optical field. To address this issue, we develop a composition engineering strategy that involves multisite selective doping. This strategy aims to transform nearly all Ce3+ into fast-emitting Ce4+ while synergistically suppressing the electron traps. Even at very low doping concentrations, the designed Ca2+, Al3+, and Ce3+ tridoped oxyorthosilicate exhibits a scintillation decay (τd) acceleration of 20%, accompanied by a 25% increase in light yield (LY). The ratio of emission efficiency and timing characteristics (LY/τd) can be enhanced by 56%, which realizes the perfect balance of high LY and fast τd. Our work provides a method for designing efficient, ultrafast, and controllable scintillators in multicomponent systems, thus paving the way for high-resolution radiation detection and imaging applications.

5.
J Phys Chem Lett ; 15(31): 7939-7944, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39074357

RESUMO

We report chemical vapor deposition (CVD) synthesis of two quasi-one-dimensional (quasi-1D) polymorphs of BiSCl, denoted by y-BiSCl and r-BiSCl. The length of the CVD samples can reach about 0.4 mm. Such quasi-1D samples of the two polymorphs can be readily separated into individual pieces for either characterization or application. The two polymorphs can be clearly differentiated by Raman spectroscopy. First-principles calculations and group analysis are used to assign each Raman peak to the corresponding vibrational mode. Ultraviolet-visible measurements on solution grown thin-film samples reveal that the two polymorphs exhibit significantly different band gaps of 2.08 eV (y-BiSCl) and 1.81 eV (r-BiSCl). First-principles calculation further shows that the interatomic chain binding energy is 18.1 meV/Å2, confirming that the van der Waals stacking determines the difference in their band gaps. Our findings highlight the possibility of realizing the desired functionalities in quasi-1D materials by controlling stacking orientation.

6.
Mar Pollut Bull ; 206: 116737, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39053263

RESUMO

Hexabromocyclododecanes (HBCDs) are legacy additive brominated flame retardant. In present study, the distribution, biomagnification and potential human health risk associated with HBCDs were investigated in six edible marine fish species collected from three bays in the Beibu Gulf, China, between March and October 2021. The concentration of HBCDs ranged from 0.05 to 200 ng/g lipid weight (lw), with Scoliodon laticaudus and Trichiurus nanhaiensis having the highest and lowest concentration, respectively. The α-HBCD was dominant in most studied fish, expect for Scoliodon laticaudus. Dietary source was the primary factor for the diastereomeric profiles of HBCDs in fish. Only γ-HBCD demonstrated trophic magnification in the studied fish species. Finally, the estimated daily intake (EDI) was 0.18 ng/kg/day for adults, 0.17 ng/kg/day for teenager and children, and all corresponding margin of exposure (MOE) values were lager than 8 indicating relatively low human exposure risks from fish consumption.


Assuntos
Peixes , Hidrocarbonetos Bromados , Alimentos Marinhos , Poluentes Químicos da Água , Animais , Hidrocarbonetos Bromados/análise , China , Poluentes Químicos da Água/análise , Humanos , Exposição Dietética , Retardadores de Chama , Contaminação de Alimentos/análise , Monitoramento Ambiental , Medição de Risco
7.
IEEE Trans Cybern ; 54(1): 209-218, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37027565

RESUMO

3-D Morphable model (3DMM) has widely benefited 3-D face-involved challenges given its parametric facial geometry and appearance representation. However, previous 3-D face reconstruction methods suffer from limited power in facial expression representation due to the unbalanced training data distribution and insufficient ground-truth 3-D shapes. In this article, we propose a novel framework to learn personalized shapes so that the reconstructed model well fits the corresponding face images. Specifically, we augment the dataset following several principles to balance the facial shape and expression distribution. A mesh editing method is presented as the expression synthesizer to generate more face images with various expressions. Besides, we improve the pose estimation accuracy by transferring the projection parameter into the Euler angles. Finally, a weighted sampling method is proposed to improve the robustness of the training process, where we define the offset between the base face model and the ground-truth face model as the sampling probability of each vertex. The experiments on several challenging benchmarks have demonstrated that our method achieves state-of-the-art performance.

8.
J Environ Sci (China) ; 127: 577-588, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36522087

RESUMO

Soil salinity is known to improve cadmium (Cd) mobility, especially in arid soils. However, the mechanisms involved in how salt stress-associated metabolic profiles participate in mediating Cd transport in the soil-plant system remain poorly understood. This study was designed to investigate the effects of salinity-induced changes in soil metabolites on Cd bioavailability. Sodium salts in different combinations according to molar ratio (NaCl:Na2SO4=1:1; NaCl:Na2SO4:NaHCO3=1:2:1; NaCl:Na2SO4:NaHCO3:Na2CO3=1:9:9:1; NaCl:Na2SO4:NaHCO3:Na2CO3=1:1:1:1) were applied to the Cd-contaminated soils, which increased soil Cd availability by 22.36% and the Cd content in wheat grains by 36.61%, compared to the control. Salt stress resulted in soil metabolic reprogramming, which might explain the decreased growth of wheat plants and increased Cd transport from the soil into wheat tissues. For example, down-regulation of starch and sucrose metabolism reduced the production of sugars, which adversely affected growth; up-regulation of fatty acid metabolism allowed wheat plants to maintain a normal intracellular environment under saline conditions; up-regulation of the tricarboxylic acid (TCA) cycle was triggered, causing an increase in organic acid synthesis and the accumulation of organic acids, which facilitated the migration of soil Cd into wheat tissues. In summary, salt stress can facilitate Cd transport into wheat tissues by the direct effect of salt-based ions and the combined effect of altered soil physicochemical properties and soil metabolic profiles in Cd-contaminated soils.


Assuntos
Poluentes do Solo , Solo , Solo/química , Cádmio/química , Triticum/metabolismo , Poluentes do Solo/análise , Cloreto de Sódio , Estresse Salino
9.
J Colloid Interface Sci ; 633: 897-906, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36508397

RESUMO

Electrocatalytic water splitting to generate high-quality hydrogen is an attractive renewable energy storage technology; however, it is still far from becoming a real-world application. In this study, we developed an effective and stable nickel foam-supported Fe2P@CoMnP4 heterostructure electrocatalyst for overall water splitting. As expected, the as-obtained Fe2P@CoMnP4/NF electrocatalyst exhibits superb bifunctional catalytic activity and only requires extremely low overpotentials of 53 and 249 mV to achieve a current density of 10 mA cm-2 for the hydrogen and oxygen evolution reactions, respectively. Moreover, a two-electrode electrolyzer assembled using Fe2P@CoMnP4/NF as electrodes operates at the low cell voltage of 1.54 V at 10 mA cm-2, showing excellent long-term stability for 140 h. Theoretical calculations indicate that the surface electronic structure is effectively adjusted by the generated heterointerfaces between the Fe2P and CoMnP4 in a two-phase matrix, resulting in a Gibbs free energy of hydrogen adsorption close to zero and high intrinsic activity. This innovative strategy is a valuable route for producing low-cost high-performance bifunctional electrocatalysts for water splitting.

10.
Chem Commun (Camb) ; 58(64): 8966-8969, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35861224

RESUMO

A mild, selective and redox-neutral Cp*Ir(III)- and Cp*Rh(III)-catalyzed C-H activation/annulation of salicylaldehydes with fluorovinyl tosylates is reported. The use of monofluorovinyl tosylate favors the synthesis of C2- and C3-substitution-free chromones via C-H activation/ß-F elimination/annulation, whereas difluorovinyl tosylate leads to the construction of C2-fluoroalkoxy chromones. Mild reaction conditions and good functional-group tolerance were observed. Further functionalization of the resulting chromones via halogenation, alkynylation, alkylation and hydrocyanation was successfully realized.


Assuntos
Cromonas , Aldeídos , Alquilação , Catálise , Estrutura Molecular
11.
Sci Total Environ ; 847: 157604, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-35901892

RESUMO

The unsteady comprehensive system of pe + pH strongly affects the fate of Cd in paddy soils. However, the specific pe + pH threshold determining Cd bioavailability is largely unknown especially considering the roles of Fe and S reduction. The experiment set different water managements to obtain paddy soil samples with unstable pe + pH, and chemical analysis, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) characterization were applied to reveal the dynamic process and mechanism about how Fe and S controlled Cd mobilization. The results showed that low pe + pH was favorable to soil Cd immobilization. Compared with high and medium pe + pH, the exchangeable Cd content decreased by 67.57 % and 64.71 % at low pe + pH, respectively. The XPS results showed that the contents of Fe(II) and S(-II) increased to 65.1 % and 75.2 % at low pe + pH condition, which was higher than that in other treatments. In the process of flooding for reducing Cd mobility, first it was attributed to the formation of amorphous iron oxides that can provide amount of adsorption sites for Cd. After then, S2- began to play a dominant role to combine with Cd2+ to form CdS with continuous decreased pe + pH. Therefore, Fe and S played the different dominant roles on Cd immobilization in paddy soil, and soil pe + pH value could work as a threshold.


Assuntos
Oryza , Poluentes do Solo , Cádmio/análise , Compostos Ferrosos/metabolismo , Concentração de Íons de Hidrogênio , Ferro/análise , Oryza/química , Solo/química , Poluentes do Solo/análise , Água/análise
12.
Sci Total Environ ; 847: 157622, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-35901894

RESUMO

Aging of pollutants determines bioavailability and toxicity thresholds of environmental pollutants in soil. However, the ecotoxicity of chromium (Cr) rarely considers the effect of aging as well as soil properties. In order to explore the aging characteristics and establish their quantitative relationship with different soil properties, this study selected 7 soils with different properties through exogenous addition of Cr and determined its toxicity on barley root elongation. From 14d to 540d, EC10 and EC50 of barley root elongation ranged from 21.40 to 312.52 (mg·kg-1) and 50.15 to 883.88 (mg·kg-1) respectively. The hormesis appeared in the dose-response curve of acid soil as relative barley root elongation reached >110 % compared with the control. Extended aging time of Cr from 14d to 540d was associated with the attenuation of the toxicity of Cr, as the aging factor increased from 1.26 to 6.09 for EC50, from 0.88 to 4.98 for EC10. The prediction model of AFEC50 and soil properties is lg (AF360d) = 0.306lg Clay+0.026lg CEC + 0.240 (R2 = 0.872, P < 0.01). The results demonstrated that with the extension of aging time, the toxicity of Cr decreased at 360d and reached a slow reaction stage, after that soil OC, Clay and CEC could well explain the aging procedure of Cr (VI). These results are beneficial for risk assessment of Cr contaminated soils and establishment of a soil environmental quality criteria for Cr.


Assuntos
Hordeum , Poluentes do Solo , Cromo/toxicidade , Argila , Solo , Poluentes do Solo/análise
14.
Bull Environ Contam Toxicol ; 109(2): 286-297, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35391544

RESUMO

This study investigated the effects of different types of saline stress on the availability of cadmium (Cd) and bacterial growth. Changes in soil physicochemical properties and DTPA-Cd content as well as microbial responses after the addition of salts were measured. The addition of 18 g kg-1 of salts with NaCl and Na2SO4 increased the available Cd content by up to 17.80%-29.79%. Respiration rate, biomass, and relative bacterial growth decreased with increasing salt concentrations. Estimated salinity tolerance of bacterial communities based on pollution-induced community tolerance. The salinity tolerance index EC50 of the bacterial community was estimated by logistic equation and ranged from 4.32-12.63 g kg-1. Structural equation modeling showed that soil salinity stress significantly affected Cd availability and bacterial community, while bacterial growth characteristics also contributed to reducing available Cd. We conclude that saline stress can alter soil Cd availability in soils by affecting the growth characteristics of soil bacterial communities.


Assuntos
Poluentes do Solo , Solo , Bactérias , Cádmio/química , Cádmio/toxicidade , Salinidade , Sais , Cloreto de Sódio , Solo/química , Microbiologia do Solo , Poluentes do Solo/química , Poluentes do Solo/toxicidade
15.
Sci Total Environ ; 833: 155182, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35417729

RESUMO

The environmental risk threshold of a pollutant is a yardstick to measure soil environmental quality. The derivation of ecological risk thresholds of the heavy metal zinc (Zn) in soil environments based on up-to-date ecological risk assessments plays an important role in soil protection policy. According to regional soil classification, different representative soils with various degrees of acidity and alkalinity were selected, and a data set comprising ecotoxicities of Zn to 21 different test endpoints (plants, soil fauna, microorganisms, etc.) found in representative farmland soils of China was compiled based on new and published data to determine toxicological limits of Zn effects on endpoints. These limits were derived from fitted dose-response model parameters and indicated by EC10 values (the effective concentrations of Zn that inhibit 10% of endpoint bioactivity and also represents the toxicity threshold of Zn in this study) ranging from 36 mg·kg-1 to 682 mg·kg-1. The hormesis effect appeared in the dose-response curve of Zn, for example, the relative Chinese cabbage growth reached more than 120% at most. Zn concentrations added in toxicity tests were also corrected for aging and leaching effects in order to more accurately reflect field conditions. The hazardous concentrations for 5% of the species affected (HC5) were derived by the species sensitivity distribution (SSD) approach for four major types of Chinese soils: acidic (38 mg·kg-1), neutral (106 mg·kg-1), alkaline (217 mg·kg-1), and alkaline calcareous soils (155 mg·kg-1). Prediction models of ecological risk thresholds for Zn based on soil properties were generated, such as logHC5 = 0.564 + 0.218pH + 0.097OC (R2 = 0.790,p < 0.001). The predicted models based on lab test data were verified in the field, and the measured field data fell within two-fold of the prediction intervals. This work provides a scientific framework for developing soil-specific guidance on Zn toxicity thresholds.


Assuntos
Metais Pesados , Poluentes do Solo , Plantas , Medição de Risco , Solo/química , Poluentes do Solo/análise , Zinco/análise
16.
Ecotoxicol Environ Saf ; 228: 112999, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34798362

RESUMO

Currently, the scientific basis for establishing soil environmental criteria is lacking. In order to establish reasonable soil environmental criteria values suitable for soils with different properties, this study selected soils from 16 different sites to determine the toxicity threshold of Zn based on toxicity tests of barley root elongation. In addition, leaching treatments were set up in seven soils with different properties to eliminate the influence of the accompanying anions (Cl-) on the determination of the Zn toxicity threshold. The results indicated that the toxicity thresholds of different soils vary greatly. The EC10 and EC50 ranges of barley root elongation in 16 kinds of non-leached soils were 18.5 mgkg-1 to 1618.7 mgkg-1 and 277.9 mgkg-1 to 3179.8 mgkg-1, respectively. The hormesis effect appeared in the dose response of Zn, and relative barley root elongation reached more than 150%. Leaching significantly reduced the Zn toxicity in acidic soils. The variation ranges of the leaching factor (LF) in the seven soils were LF10 = 1.1-9.3, LF50 = 1.0-3.2. The LF prediction model indicated that pH explained 81.4% of the LF variation (p < 0.01). The soil pH, cation exchange capacity (CEC), and conductivity (EC) explained 97.8% of the EC50 variation in the leached soil (p < 0.01). The results provide reference values for Zn environmental criteria.

17.
J Hazard Mater ; 416: 126079, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492898

RESUMO

Periodic flooding in paddy soils impacts redox behavior and induces variations in pe+pH levels. Manganese (Mn) is capable of reducing cadmium (Cd) uptake by rice. However, the processes involved in how Mn alters Cd mobilization under different pe+pH environments remain poorly understood. To investigate the mechanisms of Mn-mediated soil Cd-stabilization and subsequent inhibition of Cd uptake from flooded soils, we examined Cd immobilization in soil pot incubations, transcriptional changes in Cd-transport genes, and metabolomic analyses of roots and rhizosphere soils with or without Mn application. We found a decrease in extractable Cd concentration largely depended on irrigation-associated low pe+pH, exogenous Mn enhancement of Fe-Mn (oxyhydro)oxide-mediated Cd transformation, and Cd deposition in rice Fe/Mn plaques. Mn application led to striking effects on the expression of Cd-related genes eg. IRT, HMA, and NRAMP in rice root tissue. Exposure to Mn under variable pe+pH levels resulted in metabolic reprogramming of soil and rice roots. Mn induced amino acid synthesis in rice roots, leading to rhizosphere accumulation of free L-lysine, glycine, and glutamine, which can reportedly bind metal ions, forming complexes with Cd. Thus, secreted amino acids, low pe+pH, and free Mn can together comprise a multi-faceted approach to managing Cd toxicity in rice.


Assuntos
Oryza , Poluentes do Solo , Aminoácidos , Cádmio/análise , Cádmio/toxicidade , Inundações , Concentração de Íons de Hidrogênio , Manganês , Óxidos , Rizosfera , Solo , Poluentes do Solo/análise
18.
J Hazard Mater ; 415: 125668, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34088180

RESUMO

Effect of Fe redox state caused by low soil pe+pH levels on Cd uptake by rice is unclear. Rice grown in pots of Cd-contaminated paddy soil were subjected to different irrigation regimes: flooding, intermittent flooding (Int-FL), and sustained soil moisture at 70% water holding capacity (WHC). Results showed low pe+pH (5.52 and 7.09) in flooding treatment significantly increased relative abundances of Fe-reducing bacteria (FeRB) (6.29% and 4.51%), especially members within the Clostridium, Geobacter and Desulfuromonadia genera. Stimulation of FeRB activity induced Fe(III) reduction and increased Fe2+ content in flooded soils, which promoted Cd sequestration in low-crystalline fraction of IP (IP-Feh-Cd) and Cd bonded to amorphous Fe-oxides (amFeox-Cd). The 24.9-62.4% higher amFeox-Cd content was the important factor for 20.4-44.2% lower CaCl2-extractable Cd content in flooding treatment than those in other treatments. Soil submergence reduced Cd uptake by rice at tillering and booting stages, the critical periods of Cd transport in the soil-rice system, which was attributed to the increases in dissolved Fe2+ and IP-Feh-Cd contents and decrease in CaCl2-Cd content. Therefore, maintaining flooding during the tillering and booting stages may be an effective strategy to reduce Cd uptake by rice cultivated in Cd-contaminated soil.

19.
Appl Biochem Biotechnol ; 193(8): 2516-2533, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33779932

RESUMO

The purpose of this study was to examine the efficacy of the algicidal bacterium Sagittula stellata on the cell lysis of Nannochloropsis oceanica, a microalga found in the marine environment, in order to extract intracellular valuables. Algicidal bacteria are capable of lysing algal cell walls while keeping lipids and proteins intact yet separated. We obtained these microbes from locations with consistent algae blooms and found that the bacterium Sagittula stellata displayed significant algicidal properties toward Nannochloropsis oceanica, achieving an algicidal rate of 80.1%. We detected a decrease of 66.2% in in vivo fluorescence intensity in algae cultures, obtained a recoverable crude lipid content of 23.3% and a polyunsaturated fatty acid (PUFA) ratio of 29.0% of bacteria-treated algae, and observed the lysis of the cell membrane and the structure of the nucleus of algae. We also identified the inhibited transcription of the ribulose-1,5-bisphosphate carboxylase/oxygenase small subunit (rbcS) gene and proliferating cell nuclear antigen (PCNA)-related genes and the upregulated heat shock protein (hsp) gene in algal cells during bacterial exposure. Our results indicate that Sagittula stellata effectively lysed microalgae cells, allowing the recovery of intracellular valuables. The algicidal method of Sagittula stellata on Nannochloropsis oceanica cells was confirmed to be a direct attack (or predation), followed by an indirect attack through the secretion of extracellular algicidal compounds. This study provides an important framework for the broad application of algicidal microorganisms in algal cell disruption and the production of intracellular valuables.


Assuntos
Microalgas/microbiologia , Rhodobacteraceae/crescimento & desenvolvimento , Estramenópilas/microbiologia , Microbiologia da Água
20.
J Clin Neurosci ; 85: 41-48, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33581788

RESUMO

To investigate the safety, accuracy and indications of traditional and novel cortical bone screws placement for osteoporosis lumbar spine, 4 lumbar vertebra specimens (2 males and 2 females) were used for this study. After the computed tomography scanning data of the above anatomical specimens were three-dimensional (3D) reconstructed, one side of each anatomical specimen was randomly chosen to place traditional cortical bone screws, and the other side received novel technical placement. The safety screw trajectory was designed, and a 3D navigation template complementary to the surface anatomical structure of lumbar isthmus lateral margin-vertebral plate-spinous process part was established. The designed supporting navigation template was substantialized, and the navigation template replicated different cortical bone screw trajectory at different sides of the same one lumbar vertebra. Forty cortical bone screws were firstly placed in 3D printed vertebra and then 40 were placed in real anatomical specimens. In 3D printed specimens, the success rates of screw placement with navigation template using traditional and novel techniques were both 100%. While in anatomical specimens, the success rate of screw placement using traditional and novel navigation template was 97.5% (one out of 40 went wrong). Therefore, it is safe, accurate and reliable to place traditional and novel cortical bone screws on osteoporosis lumbar spine using 3D printed navigation template. Traditional and novel screw placement methods should be flexibly applied or combined according to specific sequence and form of vertebra.


Assuntos
Imageamento Tridimensional/métodos , Neuronavegação/métodos , Osteoporose/cirurgia , Impressão Tridimensional , Fusão Vertebral/métodos , Idoso , Cadáver , Osso Cortical/cirurgia , Feminino , Humanos , Vértebras Lombares/cirurgia , Masculino , Pessoa de Meia-Idade , Parafusos Pediculares , Tomografia Computadorizada por Raios X/métodos
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